ASTRO-H (also known as Hitomi) is an X-ray astronomy satellite commissioned by the Japan Aerospace Exploration Agency (JAXA) for studying extremely energetic processes in the universe. The space observatory is designed to extend the research conducted by the Advanced Satellite for Cosmology and Astrophysics (ASCA) by investigating the hard X-ray band above 10 keV. The observatory will extend a boom holding Hitomi's hard X-ray imagers to a length of 20 feet—more than 6 meters—during the mission's commissioning phase. The rest of Hitomi's instrument suite—comprising four telescopes and four instruments—are mounted inside the spacecraft's main body. Hitomi's instruments cover a wide range of energies on the electromagnetic spectrum, from so-called 'soft' X-rays around 300 electron volts to 'soft' gamma rays up to 600,000 electron volts.